The idea is very nice, I also implemented in my game an all out powerful attack that obliterates all of the enemies on the screen, but in your game is more like an option if you charge or not which doesn't make any sense to charge the nuke cause you are better off holding the left click in my opinion.
The visuals and audio are your strongest point, but you still lack some little but important things like a feedback when you get hit, also I think the resolution is not set properly because I didn't see any UI like the NUKE charge or the player HP, if I had to guess you ran out of time considering this was submitted 14 min before the jam ended.
Overall this is still a very well polished end-product and quite fun, also HUGE respect for the guy who did the art.